Studies On The Function Of AbPbs2 Gene And The Docking Site Of Downstream MAPK Of Alternaria Brassicicola

Alternaria brassicae(A.brassicicola) is a fungi that widely distributed in the nature,and it has wide host range,strong adapt ability to the environment. It is an important plant pathogenic bacteria and saprophytic banteria common cruciferous black spot disease,often causes serious economic losses. The study found it plays an important role in the regulation of the high osmolarity glycerol signal transduction pathway in spore growth 、stress、drug resistance and pathogenicity of penetration. This research intends to study further the signal pathway of MAPK kinase(AbHog1) and PAPKK(AbPbs2) between the anchoring mechanism,figure out the anchoring site, understand comprehensively the A.brassicicola high osmotic pressure signal transduction mechanism of glycerol,deep into the understand of the molecular function of the pathogen the mechanism,provide the oretical and technical support for the devepment of an important way for new sterilization to the target agent for the future.The main results of this research are as follows.(1) Using known A.brassicae Pbs2 gene sequence and the bioinformatics software analysis, we designed the specific primers. The AbPbs2 coding region gene of DNA was obtained through PCR amplification. Analysis of the protein sequence showed that we confirmed the successful AbPbs2 gene. The unceasingly thorough research of fungi’s HOG pathway is to understand the mechanism of the metabolic pathways of the various factors and metabolic mechanism, to human full understanding and utilization of microbial resources lay the theoretical foundation. The study of cloning and the functional identification of A.brassicae AbPbs2 gene is to further study of fungal growth, pathogenicity, environmental adaptability, and it plays an important foundation.(2) AbPbs2 gene insertion mutant was constructed by protoplast transformation system.Compared to the △ AbPbs2 and wild bacteria in growth rate and sporulation capacity,sensitivity, fungicide fludioxonil resistance and pathogenicity difference of permeability, the results showed that the changes of the mycelium growth were not big, but the capacity of the spore was severely damaged, and the sensitivity of the osmotic pressure was enhanced, and the pathogenic bacteria were also largely lost. These results indicate that AbPbs2 gene is involved in the regulation of pathogen production, osmotic pressure and pathogenicregulation.(3) The D site deletion of AbPbs2 was obtained by using the SOE-PCR method.△ AbPbs2/AbPbs2 mutual complement and △ AbPbs2/AbPbs2△Dcomplement were successfully constructed through protoplast transformation system. And compared both in growth rate, sporulation capacity, sensitivity, fungicide fludioxonil resistance and pathogenicity, the results showed that the complementary AbPbs2△D, mutual complement function were not restored to the traits of wild fungus, suggesting that D locus in AbPbs2 and AbHog1 anchor fixed effect plays an important role in the process.